Synthesis, Characterization and Antimicrobial Studies of 2-{(E)- [(4-Chlorophenyl)Imino]Methyl}Phenol Schiff Base Ligand and its Cu(II) Complex

A Schiff base ligand (84% yield) was prepared by the condensation of 4-chloroaniline and salicylaldehyde in their ethanolic solutions. The corresponding Cu(II) complex (64% yield) of the prepared Schiff base was obtained by refluxing the ethanolic solution of the Schiff base. The melting point temperature of the Schiff base was found to be 138℃, while the decomposition temperature of the Cu(II) complex was found to be 209℃. Both the Schiff base and the corresponding Cu(II) complex were found to be soluble in some organic solvents but Cu(II) was insoluble in diethylether and n-hexane. The formation of the Schiff base and its Cu(II) complex was confirmed using FTIR spectroscopy. Both the Schiff base and its Cu(II) complex were found to be stable at room temperature. The antimicrobial activity of the Schiff base and its complex were tested against human pathogenic bacteria as well as fungi and the zones of inhibition were recorded. A comparative study of zone of inhibition (ZOI) values of Schiff base and its Cu(II) complex show that, the complex display higher antibacterial activity than the free ligand and this is probably due to the greater lipophilic nature of the complex, which showed 16 mm, 20 mm, 21 mm, 17 mm, 16 mm and 15 mm against Escherichia coli, Staphylococcus aureus, Streptococcus pyogenes, Aspergillus niger, Candida albicans and Mucus indicus respectively. In addition, the results showed that, the complex Cu(II) exhibited potent antibacterial activity with the reference standard ciprofloxacin and Clotrimazole.